High-temperature alarm.



W. G. PIERCE. HIGH TEMPERATURE ALARM.

APPLICATION I'ILED ROV. 4, 1909.

968,406. Patened Aug. 23, 1910` I (y I \(y 10 10 10 imm?- W/TNESSESATTORNEYS WILLIAM GEORGE PIERCE, OF KIRKWOOD, MISSOURI.

HIGH-TEMPERATURE ALARM.

Specification of Letters Patent.

Application led November 4, 1909.

Patented Aug. 23, 1910. sei-iai no. 526,219.

To all whom it may concern:

Be it known that I, VILLIAM GEORGE PIERCE, a citizen of the UnitedStates, and a resident of Kirkwood, in the county of St. Louis and StateofMissouri, have invented a new and Improved High-Temperature Alarm, ofwhich the following is a full, clear, and exact description.

This invention relates to an alarm or annunciator of the type in which avcircuit is completed through an annunciating device when thetemperature surrounding the device has been raised above a predeterminedpoint.

This device is especially useful as a lire alarm in vessels, houses,stores or the like, or to be used on journal bearings to prevent a hotbox.

An object of this invention is to provide a device which will be simplein construction, positive in its operation, inexpensive to manufacture,and not easily deranged.

A further object of this invention is to provide an annunciator having acircuit maker therein comprising two members normally held out ofcontact by means of a fusible substance which holds a spring, that isadapted to bring said members together, under tension.

These and further objects, together with the construction andcombination of parts, will be more fully described hereinafter andparticularly set forth in the claims.

Reference is to be had to the accompanying drawings forming a part ofthis speciiication, in which similar characters of reference indicatecorresponding parts in both views, and in which Figure 1 is alongitudinal section through one of the circuit makers; and Fig. 2 is adiagrammatic view illustrating the connection of a plurality of circuitmakers with an annunciator and a source of electricity.

Referring more particularly to the separate parts of the device, 1indicates a suitable annunciator or alarm, which may be in the form ofan electro-magnetic bell. Connected to one of the terminals of theannunciator 1 by a circuit 2, there is provided a suitable source ofelectricity 3, which may be in the form of an electric battery. Thelatter is connected by means of a wire 4, to one reach 5 of a parallelcircuit, the other reach of which is shown at G. The reach G isconnected by a wire 7 to the other terminal of the annunciator 1.

Arranged in parallel on the reaches 5 and 6, there are provided aplurality of circuit makers 8. Each of the circuit makers 8 has a. pairof terminals or contact members 9, which are connected to the reaches 5and G by wires l0 and 11, which are secured thereto in any well knownmanner, as by means of set screws 12 and 13.

Then the device is set for operation, the contact members 9 are securedin alinement in spaced relation by means of a pair of insulating blocks14 and 15, which are each secured to the ends of a spiral spring 16. Thespiral spring 16 is held in an extended position under tension by meansof a filling, indicated at 17, which is composed of any suitable fusiblematerial, such as a bismuth alloy, wax, rosin or the like. The contactmembers 9 are held in alinement and insulated from the spring 16 bymeans of a nonconducting hollow cylinder 18, which may be of anysuitable material, such as The whole is inclosed by a suitable casing19, which protects the same from dust and dirt. In order that the heatoutside of the casing may pass into the center of the device, so as toact on all sides of the fusible niaterial, which normally holds thesprings in an extended or strained condition, there are provided aplurality of perforations 2O in the casing 19, which extend in alinementwith similar perforations 21, in the fusible material 17. Thus any hightemperature which exists outside of the casing 19 will be communicatedto the interior and act on the fusible filling on all sides.

The operation of the device will be readily understood when taken inconnection with the above description.

In order to set the device, the spring 1G is stretched or pulled outabnormally, so as to force the contact members 19 away from each otherin spaced relation. The spaces between the coils of the spring '16 arethen lled by fusible material 17, which is suitably perforated, asdescribed above. One or more of the circuit makers are then connectedwith the annunciator l and the source of electricity 3 by suitablewires. TVhen the temperature around one of the circuit makers reaches apoint above that at which the fusible material 17 is adapted to melt. Ifthe heat is comparatively low, the material 17 will become plastic andooZe out from between the coils of the spring 1G, sufhcient space beingprovided on each side of the springs, thereby permitting the spring tocontract together, thereby drawing the vcontact members 9 intocontact,completing the circuit and exciting the annunciator l, thereby showingthat one or more of the circuit makers is heated above the danger point.If the heat is comparatively high, the material 17 may become fluid andpossibly some of it run out through the openings 20.

Any number of annunciators connected to circuit makers in differentrooms, may be put in the circuit, so that the exact location of thedanger may be quickly ascertained. This is essentially applicable in thecase of hotels or other buildings where an electric annunciator systemis used. The circuit makers can be connected into the annunciatorcircuit, thus denoting the particular room in which the danger exists,by the continuous ringing of the annunciator bell.

Having thus described my invention, I claim as new and desire to secureby Letters Patent l. A circuit maker, comprising a plurality of contactmembers, a dist-ended contractile coil spring adapted to normally urgesaid contact members into engagement, and a fusible material locatedbetween the coils of said spring, adapted to prevent the contraction ofsaid spring and thereby hold said contact members out of engagement.

2. A circuit maker, comprising' a plurality of contact members, and acylinder secured to said contact members and adapted to normally holdsaid contact members out of engagement and being composed of alternatespiral layers of springy material held under tension and fusiblematerial, said fusible material having a plurality of openingstherethrough whereby the heat without the cylinder may be communicatedinto the interior of the cylinder.

3. A circuit maker, comprising a pair of contact members extending inalinement, a cylinder secured to said contact members and adapted fornormally holding said members out of engagement and being composed of aplurality of alternate spiral layers of a spring held under tension anda fusible material, said fusible material having a plurality of openingstherein forming communicating channels between the ex-l terior of saidcylinder and the interior thereof, and a hollow non-conducting cylinderprotecting the juxtaposed ends of said contact members.

4f. In a circuit maker, the combination with a pair of contact membersextending in alinement, an insulating block secured to each of saidmembers, a spiral spring secured at its ends to said insulating blocks,and a iilling of fusible material located between t-he coils of saidspring and adapted to hold said spring under tension and also adapted tohold said contact members out of engagement with each other.

5. In a circuit maker, the combination with a pair of contact membersextending in alinement with each other in spaced relation, an insulatinghollow sleeve for protecting said contact members and holding them'inalinement, an insulating block secured to each of said contact members,a spiral spring secured at its ends to said insulating blocks, and afusible foraminated material located between the coils of said springand adapted to hold said spring in a distended condition.

6. A circuit maker, comprising a hollow tube formed of a spiral spring,a fusible material for separating the coils of said spring and holdingthem under tension, and a pair of contact members extending within saidtube and normally held out of contact with each other by said tube,means for insulating said contact members from each other,'said springbeing adapted to contract and bring said contact members into engagementwith each other when said fusible material has been exposed to a hightemperature.

7. A circuit maker, comprising a hollow cylinder and a pair of contactmembers secured to the heads of said cylinder and normally held out ofcontact with each other, said cylinder being composed of a spiral springunder tension having its coils separated by a fusible material.

S. In a circuit maker, the combination with a pair of contact members,of a tube for holding said contact members out of engagement, said tubecomprising a spiral spring under tension and a foraminated filling of afusible material located between the coils of said spring, and aforaminated casing for inclosing said tube in said contact.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

WILLIAM GEORGE PIERCE.

Witnesses:

ELEANoR WV. PIERCE, DAVID I. ZUGKER.

